Deslocamento espontâneo do núcleo do cristalino para câmara anterior / Spontaneous displacement of the lens nucleus into the anterior chamber

RESUMO Ao longo da vida, o cristalino produz novas fibras dispostas de forma concêntrica, que aumentam seu diâmetro anteroposterior e peso, tornando seu núcleo mais compacto e endurecido. A catarata hipermadura é uma forma de progressão avançada dessa proliferação de fibras, que pode desencadear uma variedade de complicações. A ruptura espontânea da cápsula anterior do cristalino, evoluindo com deslocamento anterior do núcleo, é uma complicação rara e com poucos casos publicados na literatura. Descrevemos o caso de uma paciente do sexo feminino, 68 anos, que apresentou ruptura espontânea da cápsula anterior do cristalino com deslocamento anterior do núcleo em olho esquerdo sem histórico de trauma ocular. A paciente foi submetida à facoemulsificação do cristalino e ao controle da pressão intraocular, evoluindo com melhora do quadro clínico.

ABSTRACT Throughout life, the lens produces new fibers arranged concentrically, which increase its anteroposterior diameter and weight, making its nucleus more compact and hardened. Hypermature cataract is an advanced stage of this fiber proliferation, which can trigger a variety of complications. Spontaneous rupture of the anterior lens capsule evolving with anterior displacement of the nucleus is a rare complication, with few cases published in the literature. We describe the case of a 68-year-old female patient, who presented spontaneous rupture of the anterior lens capsule with anterior displacement of the nucleus in the left eye, without a history of ocular trauma. The patient underwent phacoemulsification and clinical control of intraocular pressure, improving her condition.

Age-related appearance of lamellar structures in lens capsule of cataractous eyes and its pathological significance.

PURPOSE: To determine morphological changes in the lens capsule with aging. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. DESIGN: Cross-sectional study. METHODS: 25 eyes from the older patient group (aged 80 years or older) and 25 eyes from the younger patient group (aged 65 years or younger) who were diagnosed with cataract and indicated for surgery were included in the study. After continuous curvilinear capsulorhexis, the anterior lens capsule was collected, immediately fixed, and processed for electron microscopy analysis. Backscattered electron images of the cross-section of the anterior lens capsule were observed under a scanning electron microscope. The ultrastructure of the anterior lens capsule was observed and compared between the groups. Factors associated with the occurrence of the lamellar structure were also identified, with the presence or absence of a lamellar structure as an objective variable and preoperative clinical characteristics as the explanatory variables. RESULTS: 50 eyes of 50 patients were included. In the younger patient group, 20 eyes (80%) had a homogeneous lens capsule, whereas 5 eyes had lamellar structures. By contrast, in the older patient group, 5 eyes had homogeneous structures, while the remaining 20 eyes (80%) had lamellar structures. 1 eye showed capsular delamination. The only significant factor for the occurrence of lamellar structures was age group ( P < .01, nominal logistic regression analysis). CONCLUSIONS: Lamellar structures appear in the anterior capsule during aging. The appearance of lamellar structures indicates fragility of the lens capsule, which may, in turn, lead to capsular delamination or lens dislocation in some cases.

Lamellar Dissection Technique for Traumatic Cataract With Corneal Incarceration.

PURPOSE: To describe a technique for traumatic cataract management for cases in which part of the anterior capsule has been incarcerated into a healed corneal laceration. METHODS: This is a single-center retrospective chart review of 3 patients with capsular/corneal incarceration after penetrating injury. Each patient underwent primary globe repair, followed by subsequent cataract surgery with intraocular lens (IOL) and iris prosthesis placement. The main outcome measure was corrected distance visual acuity. RESULTS: At a mean of 19-month postoperative follow-up (range 12-26 mo), corrected distance visual acuity ranged from 20/25 to 20/80 and all patients had improved vision compared with before cataract surgery. At the final follow-up, all IOLs and iris prostheses were in stable position and no eyes required corneal transplantation. CONCLUSIONS: Traumatic cataracts may be complicated by incarceration of the anterior capsule into the cornea. Incorporating the posterior aspect of the cornea into the anterior capsulotomy enables cataract removal and IOL placement in a stable capsular bag complex.

Phacolytic glaucoma: A nearly forgotten entity.

PURPOSE: To report a case of phacolytic glaucoma with rupture of anterior lens capsule in a case of hypermature cataract. METHODS: Case report and literature review. RESULTS: An 80-year-old woman presented with cloudiness and pain in the left eye for 1 day. The patient had visual acuity limited to perception of light with raised intraocular pressure of 70 mm Hg. Careful slit-lamp evaluation revealed corneal epithelial edema in superior quadrant and a deep and turbid anterior chamber. Ultrasound biomicroscopy confirmed the presence of a deep anterior chamber, a hypermature cataractous nucleus with lax capsular bag, and ruptured anterior lens capsule. The patient underwent extracapsular cataract extraction. Cytological examination of the lenticular fluid revealed the presence of lens protein-laden macrophages. Post-operatively, the patient had best-corrected visual acuity of 6/60 with advanced glaucomatous optic neuropathy. CONCLUSION: Phacolytic glaucoma can present with a cloudy cornea and a turbid anterior chamber mimicking endophthalmitis. Careful examination and ancillary investigations including ultrasound biomicroscopy was helpful in making an accurate diagnosis.

Corneal decompensation due to spontaneous absorption of lens and anterior dislocation of lens capsule: A case report.

RATIONALE: Spontaneous absorption of lenses or cataracts is rare. However, lens capsule attachment to the endothelium combined with corneal decompensation can still occur. PATIENT CONCERNS: An 81-year-old male presented with left eye pain and bulbar conjunctival injection for 6 months. Diffuse corneal edema and inferior bullous lesions were observed by slit-lamp microscopy. Following examination with swept-source optical coherence tomography, we could clearly identify a membrane structure adherent to the corneal endothelium, as well as a lens not in situ. In vivo confocal microscopy found decreased corneal endothelial density of 745 ±â€Š46 cells per mm in the left eye. DIAGNOSIS: Lens dislocation and spontaneous absorption, combined with corneal decompensation were diagnosed. INTERVENTIONS: Surgical removal of the membrane structure combined with anterior vitrectomy was performed. OUTCOMES: The patient's symptoms were partly relieved. However, the corneal endothelial decompensation could not be entirely reversed. In vivo confocal microscopy verified that corneal endothelium was in situ and the density was not significantly changed in the left eye. LESSONS: This case study reports a rare dislocation and spontaneous absorption of lens without any trauma or subsequent surgery. Moreover, it demonstrates corneal endothelial decompensation due to the lens capsule adhering to the corneal endothelium. Timely intervention is required to remove the dislocated lens and prevent complications.

Long noncoding RNA glutathione peroxidase 3-antisense inhibits lens epithelial cell apoptosis by upregulating glutathione peroxidase 3 expression in age-related cataract.

Purpose: Age-related cataract (ARC) is the leading cause of visual impairment and blindness worldwide. The apoptosis of lens epithelial cells (LECs) induced by oxidative damage is a major contributing factor to ARC. Long noncoding RNAs (lncRNAs) play important roles in various biologic processes. We aimed to explore the role of glutathione peroxidase 3 (GPX3)-antisense (AS) in ARCs. Methods: We extracted total RNAs from transparent and age-matched cataractous human lenses and detected lncRNA expression profiles using high-throughput RNA sequencing. The expression of GPX3-AS and GPX3 was detected by quantitative real-time PCR (qRT-PCR). Apoptotic proteins were detected by western blot and immunofluorescence. We treated SRA01/04 cells with H2O2 to mimic oxidative stress and induce cell apoptosis, which was analyzed by flow cytometry and TdT-mediated dUTP Nick-End Labeling (TUNEL) assay. The cell counting kit-8 (CCK-8) assay was used to detect the viability of SRA01/04 cells. The location of GPX3-AS was determined by fluorescence in situ hybridization (FISH) and cell nuclear and cytoplasmic RNA separation. Results: The lncRNA GPX3-AS, which is located in the nuclei of LECs, was downregulated in cataractous human lenses compared with control lenses, and proapoptotic proteins were expressed at high levels in the anterior lens capsules of ARC tissues. An in vitro study suggested that GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis. As GPX3-AS is transcribed from the AS strand of the GPX3 gene locus, we further revealed its regulatory role in GPX3 expression. GPX3-AS was positively correlated with GPX3 expression. In addition, GPX3-AS inhibited H2O2-induced SRA01/04 cell apoptosis by upregulating GPX3 expression. Conclusions: In summary, our study revealed that GPX3-AS downregulated the apoptosis of LECs via promoting GPX3 expression, implying a novel therapeutic target for ARCs.

Severe Abnormalities of Lens Epithelial Cells in Exfoliation Syndrome: A Transmission Electron Microscopy Study of Patients with Age-Related Cataract.

Background and objectives: The aim of this study was to examine via electron microscopy the lens epithelial cells in age-related cataracts and compare the findings between patients with and without exfoliation syndrome, in the Greek population. Materials and Methods: Twenty-one patients with age-related cataracts, older than 60 years, were included in the study. Eleven of them also suffered from exfoliation syndrome. Anterior lens capsules, obtained during phacoemulsification, were examined with a transmission electron microscope. Results: In all cases, ultrastructural features of diffuse intracellular and extracellular oedema were noticed to a varying degree and transparent vacuoles were detected. Often, there was more than one layer of cells, giving the impression that healthier cells tried to cover neighboring cells presenting extensive damage. Commonly, cells lost their regular shape and appeared with expanded nuclei carrying dense granules. Apoptotic cells were also detected. The epithelial cells frequently were completely destroyed or absent, exhibiting loose connections amongst them or with the basement membrane. In exfoliation syndrome (XFS) patients the alterations were more severe. Additionally, the lens epithelial cells (LECs) apical cell membrane appeared with varying distances from the basement membrane, due to different cell "heights", creating an irregular margin of the epithelium (p<0.05). Conclusion: Transmission electron microscope (TEM) examination revealed ultrastructural abnormalities in all patients' lens epithelia, more extended and more frequently observed in XFS group. In all cases, the lesions were comparable to those described in severe pathologies, all of which were excluded from the study. Environmental factors such as increased ultraviolet B (UVB) radiation exposure in Mediterranean countries, genetic factors, epigenetic factors, or all of them, could contribute to these alterations. Further epidemiological and molecular biology research is needed, so as to justify these results.

Long-term follow-up of persistent low vault after implantable collamer lens exchange.

The implantable collamer lens (ICL) is a widely used posterior chamber phakic intraocular lens that achieves excellent refractive results. Nonetheless, serious postoperative complications related to inadequate vault have been previously reported. Therefore, lens exchange is advised when the vault is out of the recommended ranges. This article presents a case with persistent low vault after lens exchange in which no clinical evidence of crystalline lens opacity or decrease in uncorrected distance visual acuity has been identified during the 6-year clinical follow-up performed to date. Therefore, this suggests that clinical follow-up could be an appropriate approach for patients presenting with low vault, especially those who are older than 40 years and have a history of lens exchange.

Three-Dimensional Morphology Study of Capsule in Pseudophakic Eyes with High-Speed Swept-Source Optical Coherence Tomography.

PURPOSE: To study the capsule morphology in pseudophakic eyes on the three-dimensional level using high-speed swept-source optical coherence tomography (SSOCT). METHODS: This study collected patients with age-related cataract and divided them into two groups according to the anterior capsule and intraocular lens (IOL) optic relationship: total anterior capsule overlap (360°, Group-T) and partial anterior capsule overlap (<360°, Group-P). One standard SSOCT radial scanning was performed in all eyes at 1 day, 1 week, 1 month, and 3 months postoperatively. RESULTS: Thirty-two eyes from 25 patients were enrolled in the Group-T and 17 eyes from 13 patients in the Group-P. No eyes achieved complete adhesion between IOL optic and posterior capsule at 1 day after the surgery. However, the rate of complete adhesion was low (15/49, 30.6%) even at 3 months postoperatively and there was no statistically difference between Group-T and Group-P (21.9% vs. 47.1%, P > 0.05). At 1 day, 1 week, 1 month, and 3 months after the surgery, the capsule bend index (CBI) in the Group-T was 0.02 ± 0.09, 1.35 ± 1.48, 3.60 ± 0.54, and 3.88 ± 0.19, respectively. CBI rises linearly during the first month and the rise goes stable relatively with the great reduction of standard deviation in the following 2 months (All P < 0.05). The anterior capsule opening area and diameter were both reduced in the first month, and then they both became stable. CONCLUSIONS: With square-edge IOL, posterior capsule opacification risk is still high in most eyes at 3 months postoperatively for the complete adhesion of posterior capsule and IOL was only achieved in 30.6% eyes. IOL-in-bag may be driven by the significant capsule bag changes especially in the first month postoperatively.

New stains for anterior capsule surgery.

PURPOSE: To investigate whether new dyes and dye combinations can give equivalent or better staining in anterior capsule surgery than existing dyes with a low degree of toxicity on relevant cells. SETTING: University laboratory of Jacobs University Bremen, Germany. DESIGN: Laboratory experimental study. METHODS: Pig eyes were collected post mortem. Cataract was induced by microwave irradiation. Access to the lens capsule was through open-sky surgery. Staining was performed and results were documented by photography. The toxicity of the dyes was evaluated in 3 different cell lines immediately after exposure and with a delay of 24 hours, with exposure in the dark or subsequent strong illumination. RESULTS: A new cyanine dye, BIP (2-[5-[3,3-dimethyl-1-(4-sulfobutyl)-1,3-dihydro-indol-2-ylidene]-penta-1,3-dienyl]-3,3-dimethyl-1-(4-sulfobutyl)-3H-indolium sodium), was found to lead to green staining, with reduced toxicity on corneal endothelial cells. Staining could be further enhanced by combining it with trypan blue. Methylene blue was very toxic, whereas its combination with trypan blue was much less toxic. CONCLUSIONS: With BIP alone or in combination with trypan blue, safe staining of the capsule can be achieved, resulting in a green color.

Long-term follow-up of neodymium:YAG laser anterior capsulotomy for the treatment of anterior capsular phimosis.

Objective To investigate the long-term safety and efficacy of Nd:YAG laser anterior capsulotomy for the treatment of anterior capsular phimosis. Methods We retrospectively analyzed a consecutive case series of Nd:YAG laser anterior capsulotomy in patients with anterior capsular phimosis, who were treated between November 2012 and April 2014. Data collected included risk factors, interval between surgery and capsulotomy, best-corrected visual acuity (BCVA), and diameter of anterior capsule opening before and after Nd:YAG laser anterior capsulotomy. Results Eleven eyes of 11 patients were included in the study. The mean follow-up time was 30.1 ± 4.5 months (range: 26-42 months). At the last follow-up, the mean diameter of the anterior capsule opening was 5.1 ± 0.2 mm, which was significantly greater than the diameter before laser capsulotomy (2.2 ± 0.8 mm). BCVA remained stable or improved in nine eyes (81.8%) following capsulotomy. No patients experienced recurrence of phimosis. Conclusions In a long-term study of >2 years, we found that Nd:YAG laser anterior capsulotomy is safe and effective for the treatment of anterior capsule phimosis.

Reverse Argentinean flag sign: Intraoperative complication during capsulorhexis.

We report a case of iatrogenic creation of an excessive anterior-to-posterior gradient in the setting of an open anterior capsule during capsulorhexis. This complication shows the inverse mechanism of that observed in the Argentinean flag sign. An excessive anterior-to-posterior gradient from an exuberant ophthalmic viscosurgical device fill of the anterior chamber caused radialization of the anterior capsule during creation of a continuous curvilinear capsulorhexis in a nonintumescent lens. We describe this complication as the reverse Argentinean flag sign.

Anterior Capsule of the Lens: Comparison of Morphological Properties and Apoptosis Induction following FLACS and Standard Phacoemulsification Surgery.

PURPOSE: Comparative evaluation of morphological features of anterior capsules and apoptosis induction in epithelial cells after femtosecond laser-assisted cataract surgery (FLACS) and standard phacoemulsification surgery. METHODS: Group 1: 30 FLACS anterior capsulotomies and Group 2: 30 manual anterior continuous curvilinear capsulorhexes. All patients were operated on by the same experienced surgeon. Morphological features of the anterior capsules and apoptosis induction in epithelial cells were evaluated. RESULTS: All patients revealed a significant mean best-corrected visual acuity (BCVA) improvement 3 months after surgery, and no major intraoperative nor postoperative complications occurred. The capsular epithelium appeared to be preserved in both groups. Scanning electron microscopy analysis revealed irregular saw-tooth shaped edges in capsules from Group 1 whereas capsules from Group 2 showed regular and smooth edges. A statistically significant higher expression of the downstream apoptotic effector cleaved caspase 3 was observed in Group 1. CONCLUSIONS: The saw-tooth appearance was likely due to the progressive sequence of laser pulses on the capsule. The low energy/high frequency properties of the laser pulse, combined with an overlapped pulse pattern, resulted in highly continuous morphology of capsule edges. The higher apoptosis induction in FLACS group might be due to photodisruption-dependent plasma generation and formation of cavitation bubbles.

Iris Thickness and Severity of Neovascular Glaucoma Determined Using Swept-Source Anterior-segment Optical Coherence Tomography.

PURPOSE: To investigate the iris thickness (IT) in neovascular glaucoma (NVG) using swept-source anterior-segment optical coherence tomography (ASOCT). PATIENTS AND METHODS: In this retrospective, clinic-based, comparative study, we enrolled 20 NVG patients [11 with 360-degree angle-closure (AC)-NVG and 9 with NVG without AC] and 14 healthy age-matched controls. Horizontal scanning images of swept-source ASOCT were analyzed using software calipers in temporal and nasal angle areas. ITs at 1 and 2 mm from the pupil edge were measured using ASOCT. The relation between IT and the severity of NVG, the effects of intraocular pressure (IOP), intravitreal antivascular endothelial growth factor (anti-VEGF) injection, and panretinal photocoagulation (PRP) were assessed using linear regression analysis based on the corrected Akaike information criteria index. RESULTS: The IT was thinner in 360-degree AC-NVG patients, followed by NVG patients without AC and controls (0.33 vs. 0.48 vs. 0.57 mm at 1 mm and 0.31 vs. 0.43 vs. 0.49 mm at 2 mm; P<0.001 by ANOVA). Multiple linear regression analysis revealed that 360-degree AC-NVG patients-NVG patients without AC and controls (coefficient: -0.16), NVG patients without AC-control (-0.13) and underwent PRP (0.23) at 1 mm, 360-degree AC-NVG patients-NVG patients without AC and controls (-0.12), NVG patients without AC-controls (-0.08), underwent PRP (0.16), received anti-VEGF injection (0.05) and IOP (-0.001) at 2 mm were selected predictors to explain IT. CONCLUSIONS: IT decreases with the progression of the NVG stage and is thinnest in 360-degree AC-NVG patients. Our study suggests a new morphologic feature of NVG.

Current Concepts in True Exfoliation Syndrome.

True exfoliation syndrome is characterized by the peeling of a translucent membrane from the anterior lens capsule. The condition increases with age and despite the classic association with occupations involving intense heat, most cases are idiopathic. We have proposed a new clinical classification system dividing true exfoliation syndrome into 4 successive stages based on characteristic changes in the anterior capsule. We have also proposed a new mechanism related to iris movement and aqueous flow accounting for the capsular delamination. We have found that a detached flap occurs exclusively in areas that lack the anterior zonules. In our series of 259 consecutive patients, 47 (19.5%) patients developed primary open-angle glaucoma, 26 (10.0%) had primary angle-closure glaucoma, and 15 (5.8%) were primary angle-closure suspects. Twenty-six (10.0%) patients demonstrated spontaneous phacodonesis or anterior lens dislocation, of whom 14 also had secondary angle-closure and 2 had open-angle glaucoma. Histologic studies have shown that the lens dislocation is associated with a lack of anterior zonular support. All patients developed cataracts, predominantly nuclear sclerosis. The double-ring sign frequently occurs during capsulorhexis.